A method and apparatus for determining a motion transmission value that provides security of motion transmission between two components that transfer motion through frictional engagement. The motion transmission value provides security of motion transmission through the reaction of the motion transmitted to a change in the contact force between the components that are frictionally engaged. The contact force is modulated in a predetermined frequency range during the motion transmission, and the change in the motion transmitted during the modulation of the contact force is detected. The change in the motion transmitted is evaluated using a filtering process, and the motion transmission value is determined as the result of the evaluation.